Hitting theaters today is McG's This Means War, a frothy comedy that pits Chris Pine against Tom Hardy in the fight for Reese Witherspoon's smiley affections (best of luck there, Chris). From Arthurian legend to Bridget Jones's Diary, stories of smitten trios have flooded the popular landscape, each threesome casting its sinful shadow on boring old monogamy. For this list of 15 standouts, the door was open to hallucinations, inanimate objects, and even different species—which is not to say Ménage à Twilight was ever in the running.

Humphrey Bogart, Audrey Hepburn, and William Holden in Sabrina (1954). Billy Wilder's final Paramount film, which went on to a inspire a Sydney Pollack-directed remake, sees Audrey Hepburn play a chauffeur's daughter ever-pining for the prince (William Holden) of the family that employs her father. When she finally nabs her playboy's attention after going all Edith Piaf, he's already set to wed, and older bro Humphrey Bogart swoops in to avert disaster. Sparks fly faster than film noir bullets, and we say: Not a bad fallback.

Sometimes I hate the world because The Age of Innocence as a film is so wildly overlooked and Michelle Pfeiffer's enchanting performance was eradicated during Oscar time. This film is one of my very most favorites and the story is one that will endure. This film is how I will always remember Scorsese.

Posted by DeanD on 2013-12-30 01:05:04

"Notorious" and "Casablanca" came very close to making the cut. "Vicky Cristina" seemed just too quadrangle-ish to qualify. Thanks for chiming in, guys.Posted by R. Kurt Osenlund on 2012-02-19 16:16:14

Nice list, to which I would add "Vicky Cristina Barcelona", "The Unbearable Lightness of Being", "Design for Living", "Betrayal", "Reds", "Out of the Past", "Lady from Shanghai", "Notorious", and "Brief Encounter".Posted by felonious punk on 2012-02-19 10:06:53